Having issues with the CityBars example - not loading

Hi - thanks for the video (https://vimeo.com/36420727) I folloed it yesterday with the 90 day trial version of Sencha Designer and tried it on my localhost without success. I'm running Chrome 17.0.963.79 m which I think is the latest version.
I have a Yelp api key that I made.
I thought that because I live in a remote area that there might not be enough bars in the google zoom level of 17 so I decreased that to 5 in the hope that it would look over a large area.
I have checked on Yelp and being in the UK I noticed that the term 'Pubs' is used instead of 'Bars' so I tried that too - no luck.
Now I've downloaded the example code and tried it out of the box and with the above changes too - no luck.
I get a screen with 'CityBars' at the top and then nothing else on the screen.
I've checked the network panel in the Chrome debugger (F12) and it appears to be pinging google maps but not yelp - I'm not sure if I should be seeing any yelp activity?
From looking around in the debugger I can't see any other errors.
Any help?

Thanks Phil - I'll have a look. I've tried the 'carstore' example and that works a treat (but using json/local data).
If I highlight the main controller in the Project Inspector (called 'Business' just under 'Controllers') and then go to 'code' and then 'init' there is a some code for getting the location, getting the yelp data and then binding that to the list and showing it.

If I then change to the launch function there is no code in there - both in my code and in the downloaded example. Should I move the init code into the launch function?

Pasted from init to launch but...

I'm experiencing the simliar results. I see the mainNav bar with "CityBars" at the top, and then it looks like the mask is being applied (there's an translucent overlay) but without the "loading..." text.

When I cut and paste the code from init to the launch function of the application, I get a grey screen (possible black translucent) without the mainNav bar at the top.

I really like the Sencha Touch, and Designer products. I really want to invest the time in learning how to use this framework, as I think it is far superior to anything else on the market, but this is the second tutorial I've followed that has been out dated (the other one being Ed Spencer's talk from Senchacon 2011). It's frustrating to spend half a day on a tutorial and have it not work when you've followed the instructions.

Other than the demo not working, this is a good tutorial. I do feel more familiar with the framework, but it is very unsatisfying that it doesn't work.

Yeah I never got it to work - still working with Sencha Designer 2 on the beta trial and down to 80 ish days. Writing an example that will use a mysql database to provide data via json - more useful for my needs and so far so good... Might post it for critique once I've got a bit further...